This is an old thread, but the Canadian gun auction site
www.GunAddicts.com just celebrated its 1 year anniversary recently. In such a short time it has over 250 active listings at a time and growing daily.
It's free to use with no listing, no member or commission fees. Also there are about 20 categories to make it easy to find guns by action type.
It has a good feedback rating system like ebay and what's good about it is how fast it loads - and there are pictures!